Modern combines which are designed to harvest and thresh a relatively wide range of agricultural products necessarily must be adjustable to adapt the same to the efficient threshing of such products, regardless of type, size and kind, and the principal aim is to obtain as close as possible a 100% recovery of the desired crop product rather than discharge it with the waste that normally falls from the rearend of the combine. This is accomplished in the present invention by employing a rotatable beater and coacting beater grate which receives tailings from the normal threshing and separating sections of the rotor and concave of a combine. Although the adjustability of threshing and separating concaves with respect to the threshing and separating rotor sections is known in the art, especially for purposes of adapting the combine to effectively handle a wide variety of agricultural crop materials, it appears that attention has never previously been given to adapting any type of adjustment to the means by which the tailings are subjected to further beating and separating functions, especially to consider the differences in the crop materials being harvested at any one time by the combine.
It also is old in the art, especially in regard to conventional threshing machines, to arrange concaves with threshing spikes thereon for adjustment of at least one end thereof toward and from the threshing drum, the opposite end of said concave usually being pivoted about a fixed axis so that only one end of the concave was adjustable in a radial direction. Arrangements of this type are shown in U.S. Pat. No. 750,902 to Shelton et al, dated Feb. 2, 1904; U.S. Pat. No. 918,285 to Clark, dated Apr. 13, 1909; U.S. Pat. No. 1,449,645 to Anderson, dated Mar. 27, 1923; and U.S. Pat. No. 2,484,228 to Isay, dated Oct. 11, 1949. There also is U.S. Pat. No. 2,931,363 to Bulin, dated Apr. 5, 1960, in which a concave is mounted for adjustment of the opposite ends thereof toward and from a rotatable threshing drum by means of a pivoted lever having links extending therefrom for connection to said opposite ends of the concave, whereby pivotal movement of the lever effects such adjustment. A safety release feature also is included in said patent comprising a removable pin which permits the pivoted lever to be "dropped" for instant lowering of the concave with respect to the drum. None of these patents show any suggestion of being applied to means to operate upon tailings in a modern type of combine, such as shown in U.S. Pat. No. 3,669,125 to Rowland-Hill, dated June 13, 1972, in which a transverse beater is shown for operation upon tailings but no adjustment is provided for the grate which cooperates with the beater.